Linux vs. Windows NT and OS/2

We continue to see media blurbs and ads for both Microsoft's Windows NT and IBM's OS/2. Both promise to be the operating system that we need and to take advantages of the capabilities of the Intel 386 and beyond. In the mean time, development and use of Linux, another system that takes advantage of these capabilities, lumbers along. In this article, Bernie Thompson explores these as three alternat

The Foundations

When it comes down to it, an operating system is just a
foundation. Choose the foundation that supports the features you
need and will need in the future. But be aware of the high price in
memory, storage, and performance that these features exact.

Linux, like OS/2, is designed and optimized to run on Intel
386 and compatible CPUs. By contrast, Windows NT is designed to be
ported to many different CPUs. NT is currently available for MIPS,
DEC Alpha, and Intel 386. This independence from Intel is an
important advantage for NT, because users have more hardware
choices.

All three systems support multitasking, which is the ability
to have many programs running simultaneously. For example, it is
possible to format a disk, download a file from a BBS, and edit in
a word processor, all simultaneously. You can't do this using a
system like MS DOS, which doesn't support multitasking.

NT supports multiprocessing, which means using more than one
CPU in a single machine. An NT PC could have 2 or more processors,
all working together. Again, this means more hardware possibilities
for the NT user.

NT and Linux both support dynamic caching. Caching stores
recently used information in memory, so it is readily available if
needed again. OS/2 sets aside a pre-determined chunk of memory to
do this (typically 512K to 2MB), whereas Linux and NT will
dynamically use as much spare memory as possible. The result is
much faster disk access for Linux and NT, because the information
is often already in the cache. OS/2's inflexibility causes memory
to be wasted when not used, and memory to be used poorly when it is
scarce.

Linux, unlike OS/2 and NT, has full multiuser support. Local
users, modem users, and network users can all simultaneously run
text and graphics programs. This is a powerful feature for business
environments that is unmatched by OS/2 or NT.

Linux has security systems to prevent normal users from
misconfiguring the system. Although Windows NT isn't multiuser, it
has security checks for the individual using the machine. It is
safe to have a Linux or NT machine available for use by many
people, whereas an OS/2 user could (mis)configure the system
software.

Linux's security and multiuser features are so well developed
because they are traditional features for Unix. Since Linux is
“Unix-compatible,” it supports these same powerful features.

Every feature supported will tend to make an operating system
larger, consuming more memory and storage. Larger systems are also
slower than smaller systems when memory is scarce. So the size of a
system is an important issue.

NT is the largest of the three systems. NT's support for
portability, multiprocessing, and many other features is the cause
of its large size. Given a powerful enough machine, NT offers a set
of features that is very compelling.

Linux with X/Windows is the next smaller system. Linux itself
is very miserly, but X/Windows puts a burden on the system. For
most the graphical interface will be worth the cost in
resources.

OS/2 is smallest of the three when using a graphical
interface. This is the attraction of OS/2. A user need only upgrade
to 8MB of RAM to use an object-oriented interface and have a good
platform for multitasking DOS, Windows, and OS/2 programs. OS/2 is
the strongest of the three for backward compatability with DOS and
Windows. OS/2 has sold several million copies in the last two
years, primarily because of these strengths.

Linux without X/Windows is the smallest of the three. This is
a great sacrifice for many, running without graphical windows. But
by jettisoning expensive graphics, the system is smaller and faster
than OS/2 or NT will ever be. 4MB RAM, the standard configuration
for a DOS/Windows PC, is plenty for most tasks. So Linux can make
good use of a low-end 386 PC with little memory, where OS/2 or NT
either would not run, or not run well. Systems with lots of memory
will be able to use Linux's dynamic caching to achieve unusually
high performance. With 16MB RAM, almost 12MB remains to be used for
caching and running applications.

In general, the issue of size is a great strength for Linux.
Linux was designed to be as small and efficient as possible. NT's
most important criterion was portability, and OS/2's was backward
compatibility. The result is Linux is the most efficient of the
three. And because a company or individual has access to the Linux
code, it can be optimized and scaled to suit the hardware and needs
of the user. OS/2 and NT do not have this flexibility.